Fig. 5. Effects of syntenin knockdown or Delta1 mutation on cell surface expression of Delta mutants. (A-F) Keratinocytes transduced with DeltaFl and pRetrosuper control vector (A-C) or syntenin siRNA (Rnai1; D-F) were double labelled with anti-DeltaD (green A,D) and anti-syntenin (red B,E) antibodies. (C,F) Merged images of middle and left panels. Bar, 20 µm. (G-O) Primary human keratinocytes transduced with DeltaFl, DeltaDS or DeltaVA were incubated with an anti-Delta antibody at 4°C (t=0), then transferred to fresh medium at 37°C for the times indicated. Bars, 50 µm. (P) Percentage of cells with Delta antibody at the plasma membrane. Data are means ± s.e.m. of three independent experiments. 100 cells of each type were counted per experiment. (Q) Western blot of keratinocytes transduced with ev, DeltaFl, DeltaDS and DeltaVA constructs, probed with antibodies to Zf-Delta, syntenin and actin.